Climate change concerns, high oil prices and increasing government support are some of the driving reasons of increasing renewable energy legislation, incentives, and commercialization. Hydroelectricity is the most widely used form of renewable energy and refers to electricity generated by hydropower. In this study, a storage facility is proposed to store some additional water and increase the profitability of the existing Birkapili Hydroelectric Power Plant. The storage facility is composed of a gravity dam and an uncontrolled spillway. With the help of the proposed storage facility, maximum utilization of the water is provided and shift of the electricity generation to peak demand periods becomes possible. Consequently, feasibility of the existing power plant is improved. A number of alternatives for a spillway are taken into account and the corresponding concrete gravity dam is designed. Stability analyses and operation studies are conducted using spreadsheets to achieve an economical solution.

Quality of municipal water is sustained by addition of disinfectant, generally chlorine, to the water distribution network. Because of health problems, chlorine concentration in the network is limited between maximum and minimum limits. Cancerogenic disinfectant by-products start to occur at high concentrations so it is desired to have minimum amount of chlorine without violating the limit. In addition to the health issues, minimum injection amount is favorable concerning cost. Hence, an optimization model is necessary which covers all of these considerations. However, there are uncertain factors as chlorine is reactive and decays both over time and space. Thus, probabilistic approach is necessary to obtain reliable and realistic results from the model. In this study, a linear programming model is developed for the chance constrained optimization of the water distribution network. The objective is to obtain minimum amount of injection mass subjected to maintaining more uniformly distributed chlorine concentrations within the limits while considering the randomness of chlorine concentration by probability distributions. Network hydraulics and chlorine concentration computations are done by the network simulation software, EPANET.

&Ccedil / amlidere Dam supplies significant portion of the potable water demand of the City of Ankara. Consequently, it is very important that the pipelines extending over 60 km between the dam and the treatment plant at Ivedik operate continuously. At present, two composite parallel lines are in operation and construction of a third line is considered for the future. It is the aim of this study to investigate the water hammer problems to be expected under various scenarios and also suggest the safe operation conditions for the system. Water hammer analyses of the pipeline are carried out by computer software named HAMMER. This software employs the Method of Characteristics (MoC) which is a widely used mathematical procedure in solving the non-linear differential equations caused by unsteady flow. Within this theses work, existing tunnels, prestressed concrete and steel pipes, third steel pipeline which is planned to be constructed in the future and existing, and future-planned valves are modeled and calibration of the model is implemented. A plenty of scenarios and valve closure principles are constituted in order to specify steady-state conditions and additional water hammer pressures generated by several excitations through the pipeline. Results of these scenarios are compared with previous works conducted on the pipeline system and the most unfavorable ones among those are determined. Then, appropriate closure durations are identified and suggested for pipe fracture safety valves and the flow control valves at Ivedik in order not to cause excessive pressures in the system.

Foundations of river bridges need to be protected with respect to excessive scouring. Degree of protection depends on the severity of scouring action around bridge piers and abutments. A case study is carried out to design appropriate protective measures for sequential viaducts located on Ankara-Pozant highway in Turkey. A number of analyses are conducted to obtain water surface profiles throughout the study reach. Local scour depths at piers and abutments of the viaducts are then obtained. The design process for countermeasures is performed concerning hydraulic, hydrologic, constructional, and economical requirements. To this end, riprap, partially grouted riprap, and articulated concrete blocks are studied in these view points. A criterion based on a selection index, which is defined by the National Cooperative Highway Research Program in the USA, is applied in this study. Implementation of partially grouted ripraps at infrastructural elements is found to be an appropriate solution.

The pitch trim actuator is a hydraulic powered electro-mechanical flight control device of UH-60 helicopters which converts a mechanical input and an electrical command into a mechanical output with trim detent capabilities. In this thesis study, pitch trim actuator is investigated and a mathematical model is developed. From these mathematical equations, the actuator is modeled in MATLAB Simulink environment. While constructing the mathematical model, pressure losses in hydraulic transmission lines and compressibility of hydraulic oil are considered. To achieve a more realistic model for valve torque motor, particular tests are carried out and the torque motor current gain and the stiffness of torque motor flexure tube and the flapper displacement are obtained. Experimental data to verify the Simulink model is acquired with KAM-500 data acquisition system. A test fixture is designed for acquiring the experimental data. This test fixture can also be used to test the pitch trim actuator during depot level maintenance and overhaul. To verify the consistency of Simulink model, acquired experimental data is implemented in Simulink environment. The output of Simulink model simulation and the experimental data are compared. The results of comparison show that the model is good enough to simulate the steady state behavior of the actuator.

Intakes are inlet structures where fluid is accelerated to a certain flow velocity to provide required amount of water into a hydraulic system. Intake size and geometry affects the formation of flow patterns, which can be influential for hydraulic performance of the whole system. An experimental study is conducted by measuring velocity field in the hydraulic model of the head pond of a hydropower plant to investigate vortex formation. Vortex strength based on potential flow theory is calculated from the measured velocity field. It was shown that vortex strength increases with the submergence Froude number. The free surface flow in the head pond is simulated using Flow-3D software. Vortex strength calculations are repeated using the computational velocity distributions and compared to experimentally obtained values. Similar computations were carried on with some idealized pond geometries such as rectangular and circular.

A study of the hydraulic jump on a trapezoidal prismatic channel and roughened beds is presented. Extensive measurements have been made regarding the characteristics of hydraulic jumps as sequent depths, wing fluctuations, energy dissipation and jump length on artificially roughened beds for Froude numbers between 4.16 and 14.58. Three different types of prismatic roughness elements and nine different roughness patterns were installed separately on channel bottom and side walls throughout the experiments to obtain rough surfaces. Strip roughness elements were built from fiberglass sheets and implemented perpendicular to the flow direction. To avoid cavitation, roughness elements were designed in that way that the crests of the elements are not protruding into the flow. The founded properties were compared with the available data in literature and with the properties of hydraulic jump occurred on smooth bed.

The theoretical stability analysis of mold level control system for slab continuous casting machine is presented in this thesis. In the procedure of analyzing the stability of the mold level control system, the PLC program written for the control system is studied first in order to obtain the mathematical model of a PID controller. Then the mathematical models of servo-amplifier, servo-valve, electro hydraulic system to the output of mold level are established. A simulative control system using Matlab software is constructed in accordance with these mathematical models so that not only the results of stability analysis can be verified but also the dynamic response of controlled system can be studied. Finally, the effects of some potential disturbance on system¡¦s dynamics, stability, and control accuracy are also analyzed.

District Cooling Systems (DCS) have been widely applied in large institutions such as universities, government facilities, commercial districts, airports, etc. The hydraulic system of a large DCS can be complicated. They often stem from an original design that has had extensive additions and deletions over time. Expanding or retrofitting such a system involves large capital investment. Consideration of future expansion is often required. Therefore, a thorough study of the whole system at the planning phase is crucial. An effective hydraulic model for the existing DCS will become a powerful analysis tool for this purpose. Engineers can use the model to explore alternative system configurations to find an optimal way of accommodating the DCS hydraulic system to the planned future unit. This thesis presents the first complete procedure for the use of commercial simulation software to construct the hydraulic model for a large District Cooling System (DCS). A model for one of the largest DCS hydraulic systems in the United States has been developed based on this procedure and has been successfully utilized to assist its master planning study.

With the rapidly increasing demand for energy and the increasing prices for oil and gas, the role of unconventional gas reservoirs (UGRs) as energy sources is becoming more important throughout the world. Because of high risks and uncertainties associated with UGRs, their profitable development requires experts to be involved in the most critical development stages, such as drilling, completion, stimulation, and production. However, many companies operating UGRs lack this expertise. The advisory system we developed will help them make efficient decisions by providing insight from analogous basins that can be applied to the wells drilled in target basins. In North America, UGRs have been in development for more than 50 years. The petroleum literature has thousands of papers describing best practices in management of these resources. If we can define the characteristics of the target basin anywhere in the world and find an analogous basin in North America, we should be able to study the best practices in the analogous basin or formation and provide the best practices to the operators. In this research, we have built an advisory system that we call the Unconventional Gas Reservoir (UGR) Advisor. UGR Advisor incorporates three major modules: BASIN, PRISE and Drilling & Completion (D&C) Advisor. BASIN is used to identify the reference basin and formations in North America that are the best analogs to the target basin or formation. With these data, PRISE is used to estimate the technically recoverable gas volume in the target basin. Finally, by analogy with data from the reference formation, we use D&C Advisor to find the best practice for drilling and producing the target reservoir. To create this module, we reviewed the literature and interviewed experts to gather the information required to determine best completion and stimulation practices as a function of reservoir properties. We used these best practices to build decision trees that allow the user to take an elementary data set and end up with a decision that honors the best practices. From the decision trees, we developed simple computer algorithms that streamline the process.